Tuesday, March 3, 2015

The New Black

Recently I've been lamenting the loss of a maple tree in my backyard.  A poor choice to begin with, after years of slow decline in less than ideal conditions it became clear we needed to remove it or chance damage to the house in the next bout of high winds.

  Leaves on one large branch looked anemic one year, then small branches began to slough off.  Local woodpeckers began to do their little feasting circle hops around a main trunk, and near the end the tree began to weep black streaks of sap.

This was my introduction to bacterial cankers in trees.


Since then, on walks with my dog I've started looking for signs of the canker in other trees throughout my neighborhood.  Unfortunately, I've found it.  These are photos of a neighbor's damaged live oak, proof that even our native trees are suffering.  


This link from the Forest Service says that Hypoxylon Canker is not the cause of tree death.  However, the fungus will infect the sapwood of trees that have been stressed by drought, heat, nutritional deficiencies, soil compaction, or a list of other conditions we've found all too plentiful over the past few very dry years.  

Not all bacterial cankers are the same.  This link from Penn State describes another one known to affect stone fruit trees under cool, wet conditions.

It's worth giving both of these links a visit - they're packed with information.  Thanks to my friend Jerry Naiser, owner of Arbor Consulting, Inc. and Real Green Pest and Lawn, for steering me to the Texas Forest Service site.

All material © 2015 by Vicki Blachman for Playin' Outside
Unauthorized reproduction prohibited.



3 comments:

Rock rose said...

We lost all of the main trunk of our pomegranate tree to some kind of canker. I fear that after struggling for 4 years I will have to remove it and will not be able to put another in its place. So sad to lose trees but then we are getting used to it over here as the past years of drought and heat take their toll.

Lori said...

Ohhhhh, man. This sounds familiar. I am guessing my mesquite tree that anchors the back garden is on its way out.

katina said...

Our Arizona Ash in the backyard has problems with fermenting sap - the arborists at work tell me it won't kill the tree, but it is always disconcerting to see the tree 'crying' and insects all over getting drunk as skunks. They do, however, tell me that I should be concerned about the fact that we have a 30-year-old Arizona Ash tree; my response is always, "well duh." We actually have started with the long process of removal for it - I think in about 5 years we'll have it completely removed; so I guess now's the time to start thinking about a replacement shade tree.